System and method for detecting valve operating conditions

Abstract

The present disclosure relates to a valve assembly including a valve moveable between an open position where hydraulic fluid flow is permitted between first and second ports of the valve and a closed position where hydraulic fluid flow is blocked between the first and second ports. A characteristic vibration is generated by turbulent hydraulic fluid flow within the valve when hydraulic fluid flow is first initiated between the first and second ports as the valve moves from the closed position toward the open position. The valve assembly also includes a controller for providing electrical current to control movement of the valve via a solenoid. The controller includes an accelerometer for sensing the characteristic vibration. The controller identifies an electrical current value of the electrical current at a time when the characteristic vibration is detected.

What is claimed is: 
     
       1. A valve assembly comprising:
 a valve moveable between an open position where hydraulic fluid flow is permitted between first and second ports of the valve and a closed position where hydraulic fluid flow is blocked between the first and second ports, wherein a characteristic vibration is generated by turbulent hydraulic fluid flow within the valve when hydraulic fluid flow is first initiated between the first and second ports as the valve moves from the closed position toward the open position; 
 a solenoid for moving the valve between the open and closed positions; and 
 a controller for providing electrical current to control movement of the valve, the controller including an accelerometer for sensing the characteristic vibration, wherein the controller identifies an electrical current value of the electrical current at a time when the characteristic vibration is detected. 
 
     
     
       2. The valve assembly of  claim 1 ,
 wherein the identified electrical current value is a first electrical current value; 
 wherein the characteristic vibration is a first characteristic vibration; 
 wherein a second characteristic vibration is generated by turbulent hydraulic fluid flow within the spool valve assembly when hydraulic fluid flow is about to be blocked between the first and second ports as the valve moves from the open position toward the closed position; and 
 wherein the controller is adapted to identify a second electrical current value of the electrical current at a time when the second characteristic vibration is detected by the accelerometer. 
 
     
     
       3. The valve assembly of  claim 2 , wherein the first and second electrical current values are different from each other. 
     
     
       4. The valve assembly of  claim 2 , wherein the controller provides electrical current to the solenoid in response to control commands from a user interface, and wherein a relationship between a position of the user interface and the electrical current provided to the solenoid varies based on whether the valve is being opened or closed. 
     
     
       5. The valve assembly of  claim 4 , wherein the first electrical current value is different from the second electrical current value, and wherein the relationship between the position of the user interface and the electrical current provided to the solenoid is designed such that the controller provides the first electrical current value to the solenoid when the user interface is in the first position during opening of the valve, and provides the second electrical current value to the solenoid when the user interface is in the first position during closing of the valve. 
     
     
       6. The valve assembly of  claim 1 , wherein the first and/or the second electrical current values is/are stored in a memory and mapped to a command input via a command interface. 
     
     
       7. The valve assembly of  claim 6 , wherein the command interface is a joystick, and the command input corresponds to a programmed position of the joystick. 
     
     
       8. The valve assembly of  claim 7 , wherein the programmed position of the joystick is the same for the first and the second electrical current values. 
     
     
       9. The valve assembly of  claim 1 , wherein the valve is a spool valve. 
     
     
       10. The valve assembly of  claim 1 , wherein the valve is a poppet valve. 
     
     
       11. The valve assembly of  claim 1 , wherein the controller is a control module that mounts to the solenoid. 
     
     
       12. The valve assembly of  claim 1 , wherein the controller is a control module that mounts to a valve manifold in which the valve is mounted. 
     
     
       13. The valve assembly of  claim 1 , wherein the valve assembly is used to control a hydraulic actuator of an off-highway vehicle. 
     
     
       14. The valve assembly of  claim 13 , wherein the off-highway vehicle is an excavator. 
     
     
       15. The valve assembly of  claim 1 , wherein the first and/or second electrical current values are stored in memory and used as base-line values, and wherein the controller determines subsequent first and/or second electrical current values and compares the subsequent first and/or second electrical current values to the base-line values.